30 Apr 2001wichai@bucc4.buu.ac.th1 310443 Management Information Systems 12. Components of...

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30 Apr 2001 wichai@bucc4.buu.ac.th 1

310443 Management 310443 Management Information SystemsInformation Systems

12. Components of Enterpri se Information Systems

Asst. Prof. Wichai Bunchua- 4E mail : wichai@bucc .buu.ac.th

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Components of Enterprise Information Systems

Hardware Programs Data Procedures People

Hardware

LANs Teleprocessing Systems Internets Backbone Networks

LAN Characteristics

Multiple microcomputers connected together

One or more file, database, or other servers

Bus ans ring topologies are common Computers within a mile or two of each

other Generally fewer than 50 computers

Teleprocessing Systems

Characteristics Processing performed by cenralized

computer Users access applications via dumb

terminals or micros emulating dum b terminals

Basic Components

- End user hardware Communication media WANs and MANs Polling Multiplexing Processing hardware

Communication Line Classifications

Line speed - - 3009600Voice grade ( bits per seco

) ppp pppppp pp ppppp(500,000 )

Line mode pppppp ppppppp

Line type pppp-pppppp pppp-pppppp ppppppp

Internets

Charateristics Multiple LANs interconnected Requires

Br i dge Gat eway Rout er

Backbone Networks

A large central network to which all the computers in an enterprise are connected

It provides the infrastructure for enterprise telecommunications

Communications backbones support at least three functions E-mail between users File transfer among computers Terminal emulation

Backbone Networks Characteristics

Network supports communications among computers of any type

Hundreds or thousands of computers and terminals possible

Wide geographic distribution possible via WAN

Programs

System programs Teleprocessing communications control Network communication control

Horizontal Market Application programs

Vertical Market Application programs - Cuustom developed Application prog

Departmental data independencies Distributed database system International data communications

Procedures

The need for controls EDP controls Management controls Organization controls Data center resource controls I/P/O controls

The Need for Controls

Fictitious sales Illegal funds transfer Theft of equipment

Types of Computer Crime

Manipulating computer input Changing computer programs Stealing data Stealing computer time Stealing computer programs

Categories of EDP Controls

Management Organizational Data center resource I/P/O

Types of Management Controls

Attend to MIS applications Manage MIS activity Follow up on problems Take control procedures seriously

Data Center Resource Control

Control access to data center Locate data center in protected environm

ent Pland and document operating procedures Protect libraries of program Plan and execute backup procedures Plan and practice recovery procedures Protect data center from natural hazards Protect international data center

I/P/O Controls

Input Documentation of authorized input f

ormat Separation of duties and authorities Verificaion of control totals - On line system input controls

I/P/O Controls (cont.)

Processing Documented operating procedures Reviews of processing logs Adequate program testingOutput Documented output procedures Control over disposition of output Users trained to examine output

People’s Roles

Four different roles Use Development Operations Management

The MIS Department

Data processing Development -- System analysts,

programmers Operation -- Operators, data-entry System support --System programmers

Data administration Data administrator (DA) Database administrator (DBA)

End-user support

30 Apr 2001wichai@bucc4.buu.ac.th1 310443 Management Information Systems 12. Components of...

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